Large capacity ink cartridge

Abstract

An improved ink cartridge comprising an ink chamber, a pressure relief chamber coupled to the ink chamber, and at least one air bleed hole coupling the pressure relief chamber to the ink chamber, the air bleed hole having a capillary dimension for creating a negative pressure on any ink in the air chamber. The pressure relief chamber is positioned below the ink chamber, the ink chamber including an opening to couple the ink cartridge to an ink head, the opening including an automatic shutoff valve, and the air bleed hole is positioned at the bottom of the ink chamber.

We claim: 
     
       1. An improved ink cartridge for providing a flow of ink to an ink head and for regulating a magnitude of pressure and a magnitude of flow of said ink comprising: an ink chamber for containing said ink;   a pressure relief chamber coupled to said ink chamber by one or more apertures provided between said pressure relief chamber and said ink chamber, at least one aperture of said one or more apertures having a capillary dimension that creates a negative pressure on said ink in said ink chamber, said pressure relief chamber and said at least one aperture of said one or more apertures providing pressure relief to said ink in said ink chamber, providing a partial vacuum on said ink in said ink chamber and regulating said magnitude of pressure of said ink and said magnitude of flow of said ink; and   coupling means for coupling said ink cartridge to said ink head.   
     
     
       2. The cartridge of claim 1 wherein said negative pressure has a magnitude and said aperture has a selected capillary dimension for controlling said magnitude of said negative pressure. 
     
     
       3. The cartridge of claim 1 wherein said one or more apertures comprises a plurality of apertures, said plurality of apertures having a selected number, and said flow of ink flows from said ink chamber to said ink head coupled to said cartridge, said flow of ink having a selected magnitude, said selected magnitude of said flow of ink being controlled by said selected number of apertures. 
     
     
       4. The cartridge of claim 1 wherein said cartridge is coupled to an ink head having ink jet nozzles therein with a selected capillary dimension, said aperture having a capillary dimension which is an order of magnitude larger than said selected capillary dimension. 
     
     
       5. The cartridge of claim 1 wherein said pressure relief chamber is positioned below said ink chamber. 
     
     
       6. The cartridge of claim 1 wherein said ink chamber has a bottom and includes said coupling means for coupling said ink cartridge to said ink head, said coupling means being positioned near said bottom of said ink chamber. 
     
     
       7. The cartridge of claim 6 wherein said aperture is positioned near said bottom of said ink chamber. 
     
     
       8. The cartridge of claim 1 wherein said ink chamber includes coupling means to couple said ink cartridge to an ink head, said coupling means including a surge suppressor. 
     
     
       9. The cartridge of claim 1 wherein said aperture has a selected capillary dimension and said ink flows from said ink chamber to said ink head coupled to said cartridge, said flow having a selected magnitude of pressure, said selected magnitude of pressure being controlled by said capillary dimension of said aperture. 
     
     
       10. An improved ink cartridge for providing a flow of ink to an ink head and for regulating a magnitude of pressure and a magnitude of flow of said ink comprising: an ink chamber containing said ink;   a pressure relief chamber coupled to said ink chamber by one or more apertures provided between said pressure relief chamber and said ink chamber, at least one aperture of said one or more apertures having a capillary dimension that creates a negative pressure on said ink in said ink chamber, said pressure relief chamber and said at least one aperture of said one or more apertures providing pressure relief to said ink in said ink chamber, providing a partial vacuum on said ink said ink chamber and regulating said magnitude of pressure of said ink and said magnitude of flow of said ink; and   coupling means for coupling said ink cartridge to said ink head, said coupling means including an automatic shutoff valve, said automatic shutoff valve having a housing, and said housing having one or more slots therein for allowing air to exit said housing.   
     
     
       11. The cartridge of claim 10 wherein said slots are vertically oriented for allowing air to exit said cartridge housing. 
     
     
       12. An improved ink cartridge for providing a flow of ink to an ink head and for regulating a magnitude of pressure and a magnitude of flow of said ink comprising: an ink chamber containing said ink;   a pressure relief chamber coupled to said ink chamber by one or more apertures provided between said pressure relief chamber and said ink chamber, at least one aperture of said one or more apertures having a capillary dimension that creates a negative pressure on said ink in said ink chamber, said pressure relief chamber and said at least one aperture of said one or more apertures providing pressure relief to said ink in said ink chamber, providing a partial vacuum on said ink said ink chamber and regulating said magnitude of pressure of said ink and said magnitude of flow of said ink; and   coupling means for coupling said ink cartridge to said ink head, said coupling means including a surge suppressor.